FIELD OF INVENTION
[0001] The present invention concerns heavy duty working equipment such as bulldozers, tractors
and the like, to be referred to hereinafter collectively as "earth moving vehicles".
BACKGROUND OF THE INVENTION AND PRIOR ART
[0002] There are many occasions where earth moving vehicles have to be employed in a hostile
environment such as, for example, during clearance of rubble from a road in the course
of fighting in built-up areas, construction of tracks in a terrain under fire and
the like. In all such operations the operators of earth moving vehicles are exposed
directly to fire or hurled objects such as rocks, and experience has in fact shown
that casualties among the operators of earth moving vehicles in hostile environments
are extremely high. It is the object of the present invention to remedy this situation.
[0003] Commercial earth moving vehicles comprise roll over protection systems adapted to
accommodate the operator and the various control means for driving and operation.
Such a protection system may comprise a roof or in some cases also a closed cab which,
however, is not bullet-proof. Thus in neither case is the operator protected against
firearms and as a rule not even against hurled rocks.
[0004] One of the principal considerations in the design of a roll over protection system
is that the operator needs to have an adequate vision field to enable him to perform
all his tasks. Accordingly if the normal roll over protection system of an earth moving
vehicle were to be replaced by an armoured, bullet-proof cab fitted with indirect
viewing means such as, for example, a periscope, the operator's vision would have
been restricted to such an extent that the earth moving vehicle would not have been
manageable anymore.
[0005] It is the object of the present invention to provide an earth moving vehicle which
affords safety to the operator against enemy fire and rollover in combination with
a satisfactory vision field.
GENERAL DESCRIPTION OF THE INVENTION
[0006] In accordance with the present invention there is provided an earth moving vehicle
comprising an add-on armoured cab removably fixed to brackets of the chassis, which
cab comprises at least one door and is adapted to accommodate at least one operator
as well as all control gear for driving and operating the vehicle, the cab further
comprising armoured window assemblies mounted in walls thereof, each of said assemblies
comprising a first, inwardly projecting frame removably holding at least one shatter-proof
glass vision block, a windshield glass pane being mounted on the outside of said first
frame; and a second, exterior frame spaced from said first frame and holding a set
of protective shutters, each swingable between an open and shut position, means being
provided for manipulating the shutters within the cab.
[0007] Preferably, at least one window assembly is provided on each of the front, rear and
side walls of the cab in order to maximize the vision field from inside the cab.
[0008] Also if desired, any of the doors of the cab may be fitted with a window assembly
as specified.
[0009] Due to the special design of the window assemblies, an earth moving vehicle comprising
an armoured cab according to the invention is versatile and can be used both for
peacetime and combat duties. During combat duty the shatter-proof glass vision blocks
are in position whereby the windows are practically bullet-proof. In case of heavy
fire all or part of the shutters may also be shut which afford additional protection.
Due to the fact that the glass blocks are removably mounted, a block that has suffered
a direct hit can easily and swiftly be replaced. Where this has to be done under fire
the protective shutter of the hit window is shut.
[0010] As vision is better without the vision blocks the latter may, for peacetime operation,
be removed altogether, leaving each window with the outer pane only.
[0011] Preferably, the window assembly will comprise mechanical wipers associated with the
outer pane.
[0012] In addition to accommodating the normal gear for driving and operating the earth
moving vehicle, the cab may also be fitted with airconditioning means, a receiver
transmitter for communication with the outside and any other accessories that may
be required.
[0013] Preferably the armoured cab of an earth moving vehicle according to the invention
will be designed to accommodate a team of two, one operator and one commander. In
such a case the cab's roof will preferably comprise a lid covered manhole to enable
the commander to emerge and operate exterior auxilary equipment such as a machine
gun, a light projector and the like.
[0014] Preferably, at least some of the armour of the add-on cab provided in accordance
with the present invention will consist of laminated wall structures comprising at
least one inner armour wall and at least one outer, perforated armour wall spaced
therefrom, said perforated wall comprising a plurality of holes evenly distributed
thereover, the size of the holes and the distance between them being within the range
of calibres of small-arms ammunition. The protective effect of such laminated structures
is based on the deflection of an oncoming bullet by the perforated plate and the formation
of a yaw angle, with the consequence that the impact of the deflected bullet on the
inner plate is weaker and less damaging than a direct hit. It has been found that
by means of such laminated armour plate assemblies it is possible to attain the same
degree of protection as by means of massive armour plates weighing about 40% more.
In this way, a significant reduction of weight is achieved which for a given engine
power is an obvious advantage.
[0015] Preferably the add-on cab according to the invention is designed as a single unit
which is mounted as a whole on the chassis and which can be removed therefrom as a
whole for repair and maintenance.
[0016] Accordingly, the invention also provides for use in the construction of an armoured
earth moving vehicle, an add-on cab fitted with window assemblies as specified.
[0017] The add-on cab according to the invention may be used for the manufacture of armoured
earth moving vehicles in the first place or for the conversion of conventional existing
earth moving vehicles with conventional roll over protection systems.
[0018] It is further preferred in accordance with the invention that an earthmoving vehicle
with an armoured cab according to the present invention should also have armour protection
for the engine, fuel and oil tanks and the hydraulic actuators and preferably such
armour protection is also designed in form of an add-on unit mounted on brackets of
the chassis.
[0019] The earth moving vehicles according to the invention may be of any conventional type
such as the four-wheel-drive type or the track or crawler type.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] For better understanding of the invention reference will now be had to the attached
drawings in which:
Fig. 1 is an elevation of an earthmoving vehicle with an add-on armoured cab according
to the invention;
Fig. 2 is a fragmentary view of a laminated armour plate used in making an add-on
cab in accordance with the invention;
Fig. 3 is a fragmentary view of another embodiment of a laminated armour plate used
in making an add-on cab in accordance with the invention;
Fig. 4 is an elevation, partly in section of a window assembly in an add-on cab according
to the invention;
Fig. 5 is a plan view of the window assembly according to Fig. 4, and
Fig. 6 is a sectionalong line VI-VI of Fig. 5.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0021] The earthmoving vehicle according to the invention shown in Fig. 1 comprises a chassis
1 mounted on two crawler units 2, an engine 3, a hydraulic blade unit 4 and a hydraulic
reaper tine unit 5. The engine 3 is protected with armour plates, such as plate 6
fitted with an armoured ventilating shutter 34 and which is swingable to enable access
to the engine for servicing. The radiator in front of the engine is also covered with
an armoured shutter (not shown).
[0022] Mounted on chassis 1 is an armoured add-on cab unit 7 comprising, inter alia, a rear
window assembly 8, two side window assemblies 9 only one of which is shown in Fig.
1, a door 10 with a window assembly 11 fitted therein, a small oblong window assembly
13 adjacent to door 10, and a front window unit (not shown).
[0023] The roof 12 of cab 7 comprises means such as hole 33 for engagement by hauling means
for mounting cab 7 on chassis 1 or for dismantling it therefrom. The chassis comprises
brackets (not shown) adapted to support cab 7 and to which the cab can be secured
e.g. by bolts and screws.
[0024] Roof 12 of cab 7 comprises a lid 14 covering a manhole through which the commander
can emerge, e.g. for observation or for operating auxiliary equipment such as a projector
or a machine gun (both not shown).
[0025] A laminated armoured wall structure of which at least part of the walls of cab 7
are made is shown in Fig. 2. As shown the structure comprises an inner armour plate
15 and an outer, perforated armour plate 16 held together by means of bars 17. The
perforated plate 16 comprises a plurality of circular holes 18 evenly distributed
thereover, the size of each hole 18 and the distance between the holes being within
the range of the calibre of small-arm ammunition projectiles. For example, the diameter
of holes 4 may be 11 mm and the distance between the holes about 5 mm; or by another
example the diameter of the holes is 16 mm and the distance between the holes is about
8 mm.
[0026] Armoured plate 15 may be made of armour steel and be for example about 10-20 mm thick
and the perforated armoured plate 16 may be made of hardened steel and be about 8
mm thick. If desired the laminated structure may comprise two armoured plates 16 bearing
on each other.
[0027] A modified laminated armour wall structure of which at least part of the walls of
cab 7 are made, is shown in Fig. 3. As shown there, the structure, which is mounted
on a base plate 35 forming part of the chassis comprises two inner armoured plates
36, 37, the former being of ordinary armour steel and the latter of high hardness
armour steel. By way of example, plate 36 may be 10 mm thick and plate 37 6 mm thick.
At a distance from plate 37 which distance may, for example, be of the order of 75
mm, there is mounted on a bracket 38 by means of a bolt-and-nut assembly 39 a perforated
blade laminate comprising two blades 40, 41, both of identical design which design
is similar to that of plate 16 in Fig. 2.
[0028] Both in the case of the laminated structure of Figs. 2 and 3 it is preferred to cover
the outer, perforated plate with a metal sheet in order to prevent the penetration
of dust into the space between the perforated and the non-perforated plates.
[0029] The window assembly shown in Figs. 4 to 6 is by way of example the assembly 11 of
door 10. The other window assemblies which are fitted in wall portions of cab 7,
such as windows 8 and 9 are of similar design.
[0030] As shown, the assembly 11 comprises a first frame 20 with an opening 21 which is
covered from the outside by a windshield glass pane 22 mounted on frame 20 by means
of brackets 23. Frame 20 comprises an inwardly extending rectangular skirt 24 holding
a plurality of shatter-proof laminated glass vision blocks 25 with the interposition
of a gasket 26 and held in position by a plurality of clamps 27 mounted on then edges
of skirt 24 and only one of which is shown.
[0031] Assembly 11 further comprises a second, outside frame 28 within which there are
pivoted a plura lity of shutters 29 which in Figs. 5 and 6 are shown in the shut
position while in Fig. 4 they are shown in the open position. The upper three shutters
29 are linked by a rod 30 and thus form a first group and the two lower ones are linked
by a rod 31 forming a second group. By means of two push-pull manipulators 32 each
pivoted by a link to one shutter, the shutters can be swingably opened and shut.
[0032] As can be seen in the broken away part in Fig. 5 the shutters comprise an inner,
perforated plate of similar design as plate 16 in Fig. 2 which causes a deflection
of the impinging bullets and formation of a yaw angle so that the impact of an oncoming
bullet on a vision block of the window assembly 11 is less damaging.
[0033] Preferably, windshield 22 is fitted with exterior wipers (not shown).
[0034] For peacetime operation the glass vision blocks are not required and they can be
easily removed by turning open clamps 27. For operation in the course of hostilities
the glass vision blocks 25 are inserted as shown in Fig. 4 and where in the course
of operation under hostile conditions a block 25 has to be replaced, the shutters
29 are shut and a damaged block is rapidly replaced. Smashing of windshield 22 under
hostile conditions is of no detrimental consequence because of the presence of blocks
25. At the end of operation a damaged windshield 22 can easily be replaced.
1. An earth moving vehicle comprising an add-on armoured cab removably fixed to brackets
of the chassis, which cab comprises at least one door and is adapted to accommodate
at least one operator as well as all control gear for driving and operating the vehicle,
the cab further comprising armoured window assemblies mounted in walls thereof, each
of said assemblies comprising a first, inwardly projecting frame removably holding
at least one shatter-proof glass vision block, a windshield glass pane being mounted
on the outside of said first frame; and a second, exterior frame spaced from said
first frame and holding a set of protective shutters, each swingable between an open
and shut position, means being provided for manipulating the shutters within the
cab.
2. An earth moving vehicle according to Claim 1 having a door with a window assembly
as defined in Claim 1.
3. An earth moving vehicle according to Claim 1 or 2 wherein at least some of the
armour of the add-on cab consists of a laminated wall structure comprising at least
one inner armour wall and at least one outer, perforated armour wall spaced therefrom,
said perforated wall comprising a plurality of holes evenly distributed thereover,
the size of the holes and the distance between them being within the range of calibres
of small-arms ammunition.
4. For use in the construction of an earth moving vehicle according to Claim 1, an
add-on cab comprising at least one door and being adapted to accommodate at least
one operator as well as all control gear for driving and operating the vehicle, the
cab further comprising armoured window assemblies mounted in walls thereof, each of
said assemblies comprising a first, inwardly projecting frame removably holding at
least one shatter-proof glass vision block, a windshield glass pane being mounted
on the outside of said first frame; and a second, exterior frame spaced from said
first frame and holding a set of protective shutters, each swingable between an open
and shut position, means being provided for manipulating the shutters within the
cab.
5. An add-on cab according to Claim 4 having a door with a window assembly as defined
in Claim 4.
6. An add-on cab according to claim 4 or 5 wherein at least some of the armour consists
of a laminated wall structure comprising at least one inner armour wall and at least
one outer, perforated armour wall spaced therefrom, said perforated wall comprising
a plurality of holes evenly distributed thereover, the size of the holes and the distance
between them being within the range of calibres of small-arms ammunition.